(1) Field of the Invention
This invention is directed toward trailerable sailboats in general and also to larger trailerable sailboats that can be transported over the public highway systems throughout the United States. Important features and methods are described which allow a sailboat to be trailerable with special considerations for convenience, operational simplicity, transportation, and expense.
(2) Description of Related Art
Historically, sailboats have provided important transportation and have more recently evolved into a significant recreation activity. As part of convenience, sailboats are commonly transported to desirable sailing locations on trailers over the US public roadway system. The trailer is used to launch the sailboat or a special crane is used to lift the boat into the water. Because sailboats always have a high sailing mast, the mast must be stored so the trailered boat will pass under bridges and fit with the US highway transportation specifications for dimensions and weight. How the mast is lowered, raised, and stored on a trailer becomes an important practical issue.
It is a distinct advantage to transport a sailboat on a trailer from the water to dry storage. This eliminates the need for an in water slip, which has the advantage of reducing cost to the owner for storage and handling. Being stored away from the harsh in-water environment also has the advantage of reducing maintenance expenses to the owner by reducing corrosion, fouling, mildew, organic growth, power use, and wear. Land storage of boats also has the advantage of releasing fewer toxins and other man made compounds into the water.
Others have considered the difficulties in raising and lowering a mast, including one that pivots. For example, U.S. Pat. Nos. 6,990,916, 6,526,901, 5,865,136, 4,718,370, and 4,624,204 all disclose various methods whereby a mast is raised and lowered. In these cases additional supporting structures, complicated mechanisms, or rigging that is not required for sailing the boat are needed to raise and lower the mast. The additional structures add weight, time, complexity, and expense to the boat operation.
A typical example of a mast raising system for a mast that pivots is U.S. Pat. No. 6,990,916 which discloses a mast stepping system with a vertical pole. The mechanism used to raise the mast is overly complicated and requires an operator to install the raising equipment. The mast support structure takes up a lot of deck space and has to be carried to, or stored on, the boat. It is very awkward for an operator to use.
Similarly, U.S. Pat. No. 5,865,136 discloses a portable crane with a winch and rigging that provides lifting force for a pivoting mast. However, the lifting mechanism is not required for sailing and must be installed and removed at each launching. The rail system described would need to be very heavy to contain the lifting and stability forces required making it unappealing for an operator to actually use.
U.S. Pat. No. 5,044,410 discloses a latching mechanism for a mast that pivots. However, no consideration is given to an easy method of raising the mast, in particular, for a mast that is too heavy for one operator to manually lift.
U.S. Pat. No. 4,934,295 discloses an unconventional A-shaped mast that is pivotally connected to the sailboat. The mast can be raised or lowered manually. However, as in other patents just described, no consideration is given to a simple method of raising the mast, in particular, for a mast that is too heavy for one operator to manually lift.
PCT publication number WO87002322 discloses a sailing boat with a separate ‘boom,’ which is more accurately described as an A-frame gin pole, that is added to the sailboat to aid in raising and lowering the mast. The so called boom is not actually used for sailing, and if placed aft of the main mast, would have to be removed for sailing. In actual use, this disclosure has serious practical limitations. The mast is prevented from tipping toward starboard or port by shrouds, or rigging. The tension in these lines must be continually adjusted when the mast is raised or lowered; otherwise even a light wind will place excessive torsion on the mast base. Another source of torsion may come from the boat being moderately tipped, such as may occur when the trailer is on a sloped surface. This is awkward and impractical and makes it difficult for a single operator to raise or lower the mast. A suggested spring adjustment is not well thought out and is illustrated non-symmetrically, without a practical explanation on how it would operate or be controlled. Finally, there are no descriptions of how the pivot points of the mast or boom should be designed to withstand any inadvertent twisting forces that will be likely be applied to the mast or boom in the raising operation.
U.S. Pat. No. 4,655,154 discloses a collapsible mast assembly for a sailboat that includes a deck mounted mast support. A pivoting mast is described but the patent does not disclose an easy method of raising the mast, in particular, for a mast that is too heavy for one operator to manually lift. The boom does not move the mast as the mast is folded over on top of the boom in the stored position.
On a conventional sailboat, the boom is mounted to the mast, above the mast base, on a universal joint. It is not practically possible to use the boom as a lever in raising the mast. The boom is unstable due to the freedom of motion provided by the universal joint.
Historically, and currently, trailerable sailboats are generally limited to sailboats having lengths of less than approximately thirty feet due to excessive width and weight of the boat, and due to the weight and complexity of the sailing rig in larger boats. The design of these relatively shorter boats does not consider important difficulties that arise in larger sailboats. Sailboats longer than approximately thirty feet, designed to customary industry proportions, have widths, drafts, or weights that exceed practical maximums for private trailers on most highways. Consequently, trailer, rigging, and launching challenges rise disproportionately as sailboats become longer than approximately thirty feet. Also, longer sailboats require special permits and/or commercial carriers for transport over land, due to their overall dimensions, and especially due to their width. These larger sailboats require substantial disassembly for transport requiring a crane to remove and position the mast.
Sailboats of the previously described patents often use hinged mast raising and lowering techniques suitable only for a smaller sailboat where the mast weight is about 25 pounds or less. When a mast is heavier than this, special tools, rigging, or mechanical leverage have become needed for a single operator to safely lift and install the mast.
A number of the previous trailerable sailboats utilize a mast that is completely removed from the sailboat and then stored horizontally on top of the sailboat during overland transport. Special mast supports are then used. This design is undesirable as modern masts for larger boats include numerous important rigging lines and electrical wiring to equipment used for sailing that must be disconnected. Also, longer trailerable sailboats have a commensurately heavier mast which makes the method of completely removing the mast from the sailboat highly undesirable. The storage of a heavy mast in this manner is very unappealing to an operator, requires a lot of time and care, makes an operator vulnerable to injury, and is likely to damage the sailboat. Sailboat operators are primarily interested in the amount of time in the water and not the amount of time needed for various preparations.
Longer, trailerable sailboats have a number of design problems that require a complete design encompassing important details due to the length and weight of the sailboat. The essential problems not previously considered as a whole are: the mast must be raised and lowered in a controlled and easy method, the overall dimensions must fit within normal overland transport requirements, and the position on a trailer must include considerations for the longer and heavier mast. The design must also consider that it is desirable to launch a sailboat within 10 to 15 minutes after arriving at a boat launch without use of a crane or other external equipment in typical weather conditions. It is especially desirable to launch the boat with only one operator. Further, it is also desired that existing equipment on the sailboat is used to the extent possible to accomplish these important functions.